#ifndef _OS_H
#define _OS_H
/********************************************************************
 *                                                                  *
 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
 *                                                                  *
 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2002             *
 * by the XIPHOPHORUS Company http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: #ifdef jail to whip a few platforms into the UNIX ideal.
 last mod: $Id: os.h,v 1.33 2003/09/02 05:11:53 xiphmont Exp $

 ********************************************************************/

#include <math.h>
#include "../ogg/os_types.h"

#include "misc.h"

#ifndef _V_IFDEFJAIL_H_
	#define _V_IFDEFJAIL_H_

	#ifdef __GNUC__
		#define STIN static __inline__
	#elif _WIN32
		#define STIN static __inline
	#else
		#define STIN static
	#endif

	#ifdef DJGPP
		#define rint(x)   (floor((x)+0.5f))
	#endif

	#ifndef M_PI
		#define M_PI (3.1415926536f)
	#endif

	#ifdef _WIN32
		#include <malloc.h>
		#define rint(x)   (floor((x)+0.5f))
		#define NO_FLOAT_MATH_LIB
		#define FAST_HYPOT(a, b) sqrt((a)*(a) + (b)*(b))
	#endif

	#ifndef FAST_HYPOT
		#define FAST_HYPOT hypot
	#endif

#endif

#ifdef HAVE_ALLOCA_H
	#include <alloca.h>
#endif

#ifdef USE_MEMORY_H
	#include <memory.h>
#endif

#ifndef min
	#define min(x,y)  ((x)>(y)?(y):(x))
#endif

#ifndef max
	#define max(x,y)  ((x)<(y)?(y):(x))
#endif

#if defined(__i386__) && defined(__GNUC__) && !defined(__BEOS__)
#  define VORBIS_FPU_CONTROL
/* both GCC and MSVC are kinda stupid about rounding/casting to int.
   Because of encapsulation constraints (GCC can't see inside the asm
   block and so we end up doing stupid things like a store/load that
   is collectively a noop), we do it this way */

/* we must set up the fpu before this works!! */

typedef ogg_int16_t vorbis_fpu_control;

static inline void vorbis_fpu_setround( vorbis_fpu_control* fpu )
{
	ogg_int16_t ret;
	ogg_int16_t temp;
	__asm__ __volatile__( "fnstcw %0\n\t"
						  "movw %0,%%dx\n\t"
						  "orw $62463,%%dx\n\t"
						  "movw %%dx,%1\n\t"
						  "fldcw %1\n\t":"=m"( ret ):"m"( temp ): "dx" );
	*fpu = ret;
}

static inline void vorbis_fpu_restore( vorbis_fpu_control fpu )
{
	__asm__ __volatile__( "fldcw %0":: "m"( fpu ) );
}

/* assumes the FPU is in round mode! */
static inline int vorbis_ftoi( double f )
{
	/* yes, double!  Otherwise,
	                                             we get extra fst/fld to
	                                             truncate precision */
	int i;
	__asm__( "fistl %0": "=m"( i ) : "t"( f ) );
	return( i );
}
#endif


#if defined(_WIN32) && !defined(_WIN64) && !defined(__GNUC__) && !defined(__BORLANDC__)
#  define VORBIS_FPU_CONTROL

typedef ogg_int16_t vorbis_fpu_control;

static __inline int vorbis_ftoi( double f )
{
	int i;
	__asm
	{
		fld f
		fistp i
	}
	return i;
}

static __inline void vorbis_fpu_setround( vorbis_fpu_control* fpu )
{
}

static __inline void vorbis_fpu_restore( vorbis_fpu_control fpu )
{
}

#endif


#ifndef VORBIS_FPU_CONTROL

typedef int vorbis_fpu_control;

static int vorbis_ftoi( double f )
{
	return ( int )( f + .5 );
}

/* We don't have special code for this compiler/arch, so do it the slow way */
#  define vorbis_fpu_setround(vorbis_fpu_control) {}
#  define vorbis_fpu_restore(vorbis_fpu_control) {}

#endif

#endif /* _OS_H */
